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1.
深空探测的不断发展,潜在的战争威胁以及核事故的发生增加了人类辐射暴露的风险.神经炎症是人体在辐射暴露后重要生理反应之一.神经炎症的发生与神经退行性疾病如阿尔茨海默病(Alzheimer’s disease,AD)和帕金森病(Parkinson’s disease,PD)密切相关.开发具有抗氧化和抗炎作用的中药对辐射引起的中枢神经系统损伤有积极意义.中药龙血竭对辐射诱导的神经炎症具有良好的治疗作用.本文总结了龙血竭在降低氧化应激水平,相关炎症因子表达和线粒体损伤中的作用.同时提出,内源性神经毒素可能加重辐射诱导的神经炎症的进程,而龙血竭可缓解这种神经炎症.  相似文献   

2.
神经退行性疾病是常见且难以治愈的疾病,给患者的生活带来了极大的不便。星形胶质细胞在神经退行性疾病中发挥重要作用。在神经退行性疾病患者神经系统中,受损的神经胶质细胞对周围的神经元可以产生毒性作用,造成神经元功能障碍,从而死亡。同时,受疾病影响产生的一些反应性星形胶质细胞可以保护神经元,清除神经元周围的有害物质,暂缓疾病的恶化。本综述将讨论星形胶质细胞在部分常见神经退行性疾病中发挥的作用,包括肌萎缩侧索硬化(amyotrophic lateral sclerosis,ALS)、阿尔茨海默病(Alzheimer’s disease,AD)和帕金森病(Parkinson’s disease,PD)。同时总结了星形胶质细胞对这些疾病发挥的共同作用,旨在进一步促进神经退行性疾病的研究进展。  相似文献   

3.
王晓民 《生命科学》2006,18(4):307-308
神经变性病是一大类严重危害人类健康的脑疑难疾病,其中以老年性痴呆(Alzheimer’s disease,AD)和帕金森病(Parkinson’s disease,PD)最为常见,具有高发病率、高患病率和高致残率的特点。我国现有1000万AD和PD病人,随着人口老龄化,50年后将会到2000万人以上。这给家庭和整个社会带来沉重的负担,势必影响中国社会的和谐和经济的可持续发展,已经并将进一步成为人口与健康领域中的重大问题。  相似文献   

4.
阿尔茨海默病(Alzheimer’s disease,AD)是一种以进行性认知障碍为临床表现的神经退行性疾病,具体发病机制尚不明确。肠道菌群失调与AD的发生密切相关,在AD的发生发展中发挥重要作用。肠道菌群可以通过神经、内分泌和免疫等通道与中枢神经系统进行交流,并且可能通过产生有害物质、分泌或调节神经递质以及诱导神经炎症等方式引起神经退行性病变。本文通过总结肠道菌群在各年龄段与认知的关系,分析肠道菌群影响AD的可能机制,以期为AD的防治提供新的研究方向。  相似文献   

5.
细胞代谢或细胞应激均可以引起DNA氧化损伤。DNA氧化损伤与神经退行性疾病的发生、发展密切相关。碱基切除修复在抵抗脑细胞DNA氧化损伤中起着重要的作用。就碱基切除修复在阿尔茨海默病(Alzheimer’s disease,AD)和帕金森病(Parkinson’s disease,PD)中的作用及其机制进行综述。  相似文献   

6.
在阿尔茨海默病(A1zheimer’s disease,AD)中微管相关蛋白tau能够产生许多异常翻译后修饰并聚集形成配对螺旋丝(paired helical filament,PHF)。这些tau的修饰包括过磷酸化、异常糖基化、截断等,其中,过磷酸化和异常糖基化是阿尔茨海默氏病等神经退行性疾病神经元纤维化的主要分子发病机制。  相似文献   

7.
唐丽莉  唐希灿 《生命科学》2005,17(4):328-335
神经营养因子是神经元在胚胎期及成熟发育期存活和发育所必需的分泌型肽类物质。由年龄、基因突变或其他因素导致的神经营养因子水平的改变可以导致神经元退行性变。神经营养因子能阻止阿尔采末病(Alzheimer’s disease,AD)患者胆碱能神经元的退行性变,改善患者的认知功能。开发神经营养因子用于治疗AD是极具前景的治疗策略。本文就各种相关的神经营养因子NGF、BDNF、NT-3、FGF及IGF的功能,以及它们在AD发病中的机制及治疗研究作一简要综述。  相似文献   

8.
背景:深空探测的不断发展,潜在的战争威胁以及核事故的发生增加了人类辐射暴露的风险。神经炎症是人体在辐射暴露后重要生理反应之一。神经炎症的发生与神经退行性疾病如阿尔茨海默氏病(Alzheimer"s disease, AD)和帕金森氏病(Parkinson"s disease, PD)密切相关。开发具有抗氧化和抗炎作用的中药对辐射引起的中枢神经系统损伤有积极意义。结论:中药龙血竭对辐射诱导的神经炎症具有良好的治疗作用。本文总结了龙血竭在降低氧化应激水平,相关炎症因子表达和线粒体损伤中的作用。同时,我们提出内源性神经毒素可能加重辐射诱导的神经炎症的进程,而龙血竭可缓解这种神经炎症。  相似文献   

9.
溶酶体离子通道蛋白异常引起溶酶体功能障碍是导致阿尔茨海默病(Alzheimer’s disease,AD)和帕金森病(Parkinson’s disease,PD)等神经退行性疾病的重要因素.溶酶体离子通道蛋白调节溶酶体内离子稳态、溶酶体膜电压以及溶酶体的酸度.溶酶体离子通道蛋白的结构或功能缺陷会引起溶酶体降解功能障碍,导致神经退行性疾病的发生发展.在这篇综述中,我们总结了各种离子通道蛋白调节溶酶体功能的过程及机制,以及离子通道蛋白异常参与神经退行性疾病的过程和机制.调节离子通道蛋白改善溶酶体的功能、促进异常聚集蛋白的清除,是神经退行性疾病治疗的潜在途径.  相似文献   

10.
Cui AL  Zhao L  Li LM  Qiao JT  Zhang C 《生理科学进展》2006,37(4):302-306
阿尔采末病(Alzheimer's disease,AD)严重威胁着老年人的健康与生存质量,由于其发病原因复杂、机制不明,目前尚缺乏有效的防治措施。Humanin是近年来发现的能特异性抑制AD相关毒性的分泌性短肽,通过自身二聚化在细胞外发挥神经保护作用。Humanin通过直接或间接作用抑制β-淀粉样蛋白(AB),以及家族性AD(FAD)基因如早老基因突变诱发的神经毒,而对AD不相关的毒性作用如凋亡诱导剂etoposide及Fas诱导的细胞死亡却不表现拮抗作用。因此,Humanin可通过特异性拮抗AD相关的神经毒而发挥重要的神经保护作用。  相似文献   

11.
Polycyclic aromatic hydrocarbons (PAHs) appear to be significant contributors to the genotoxicity and carcinogenicity of air pollution present in the urban environment for humans. Populations exposed to environmental air pollution show increased levels of PAH DNA adducts and it has been postulated that another contributing cause of carcinogenicity by environmental air pollution may be the production of reactive oxygen species following oxidative stress leading to oxidative DNA damage. The antioxidant status as well as the genetic profile of an individual should in theory govern the amount of protection afforded against the deleterious effects associated with exposure to environmental air pollution. In this study we investigated the formation of total PAH (bulky) and B[a]P DNA adducts following exposure of individuals to environmental air pollution in three metropolitan cities and the effect on endogenously derived oxidative DNA damage. Furthermore, the influence of antioxidant status (vitamin levels) and genetic susceptibility of individuals with regard to DNA damage was also investigated. There was no significant correlation for individuals between the levels of vitamin A, vitamin E, vitamin C and folate with M1dG and 8-oxodG adducts as well as M1dG adducts with total PAH (bulky) or B[a]P DNA adducts. The interesting finding from this study was the significant negative correlation between the level of 8-oxodG adducts and the level of total PAH (bulky) and B[a]P DNA adducts implying that the repair of oxidative DNA damage may be enhanced. This correlation was most significant for those individuals that were non smokers or those unexposed to environmental air pollution. Furthermore the significant inverse correlation between 8-oxodG and B[a]P DNA adducts was confined to individuals carrying the wild type genotype for both the GSTM1 and the GSTT1 gene (separately and interacting). This effect was not observed for individuals carrying the null variant.  相似文献   

12.
Type II diabetes is an established cause of vascular impairment. Particulate air pollution is known to exacerbate cardiovascular and respiratory conditions, particularly in susceptible populations. This study set out to determine the impact of exposure to traffic pollution, with and without particle filtration, on vascular endothelial function in Type II diabetes. Endothelial production of nitric oxide (NO) has previously been linked to vascular health. Reactive hyperemia induces a significant increase in plasma nitrite, the proximal metabolite of NO, in healthy subjects, while diabetics have a lower and more variable level of response. Twenty type II diabetics and 20 controls (ages 46–70 years) were taken on a 1.5hr roadway traffic air pollution exposure as passengers. We analyzed plasma nitrite, as a measure of vascular function, using forearm ischemia to elicit a reactive hyperemic response before and after exposure to one ride with and one without filtration of the particle components of pollution. Control subjects displayed a significant increase in plasma nitrite levels during reactive hyperemia. This response was no longer present following exposure to traffic air pollution, but did not vary with whether or not the particle phase was filtered out. Diabetics did not display an increase in nitrite levels following reactive hyperemia. This response was not altered following pollution exposure. These data suggest that components of acute traffic pollution exposure diminish vascular reactivity in non-diabetic individuals. It also confirms that type II diabetics have a preexisting diminished ability to appropriately respond to a vascular challenge, and that traffic pollution exposure does not cause a further measureable acute change in plasma nitrite levels in Type II diabetics.  相似文献   

13.
Oxidative stress-induced DNA damage by particulate air pollution   总被引:14,自引:0,他引:14  
Risom L  Møller P  Loft S 《Mutation research》2005,592(1-2):119-137
Exposure to ambient air particulate matter (PM) is associated with pulmonary and cardiovascular diseases and cancer. The mechanisms of PM-induced health effects are believed to involve inflammation and oxidative stress. The oxidative stress mediated by PM may arise from direct generation of reactive oxygen species from the surface of particles, soluble compounds such as transition metals or organic compounds, altered function of mitochondria or NADPH-oxidase, and activation of inflammatory cells capable of generating ROS and reactive nitrogen species. Resulting oxidative DNA damage may be implicated in cancer risk and may serve as marker for oxidative stress relevant for other ailments caused by particulate air pollution. There is overwhelming evidence from animal experimental models, cell culture experiments, and cell free systems that exposure to diesel exhaust and diesel exhaust particles causes oxidative DNA damage. Similarly, various preparations of ambient air PM induce oxidative DNA damage in in vitro systems, whereas in vivo studies are scarce. Studies with various model/surrogate particle preparations, such as carbon black, suggest that the surface area is the most important determinant of effect for ultrafine particles (diameter less than 100 nm), whereas chemical composition may be more important for larger particles. The knowledge concerning mechanisms of action of PM has prompted the use of markers of oxidative stress and DNA damage for human biomonitoring in relation to ambient air. By means of personal monitoring and biomarkers a few studies have attempted to characterize individual exposure, explore mechanisms and identify significant sources to size fractions of ambient air PM with respect to relevant biological effects. In these studies guanine oxidation in DNA has been correlated with exposure to PM(2.5) and ultrafine particles outdoor and indoor. Oxidative stress-induced DNA damage appears to an important mechanism of action of urban particulate air pollution. Related biomarkers and personal monitoring may be useful tools for risk characterization.  相似文献   

14.
Lewtas J 《Mutation research》2007,636(1-3):95-133
Combustion emissions account for over half of the fine particle (PM(2.5)) air pollution and most of the primary particulate organic matter. Human exposure to combustion emissions including the associated airborne fine particles and mutagenic and carcinogenic constituents (e.g., polycyclic aromatic compounds (PAC), nitro-PAC) have been studied in populations in Europe, America, Asia, and increasingly in third-world counties. Bioassay-directed fractionation studies of particulate organic air pollution have identified mutagenic and carcinogenic polycyclic aromatic hydrocarbons (PAH), nitrated PAH, nitro-lactones, and lower molecular weight compounds from cooking. A number of these components are significant sources of human exposure to mutagenic and carcinogenic chemicals that may also cause oxidative and DNA damage that can lead to reproductive and cardiovascular effects. Chemical and physical tracers have been used to apportion outdoor and indoor and personal exposures to airborne particles between various combustion emissions and other sources. These sources include vehicles (e.g., diesel and gasoline vehicles), heating and power sources (e.g., including coal, oil, and biomass), indoor sources (e.g., cooking, heating, and tobacco smoke), as well as secondary organic aerosols and pollutants derived from long-range transport. Biomarkers of exposure, dose and susceptibility have been measured in populations exposed to air pollution combustion emissions. Biomarkers have included metabolic genotype, DNA adducts, PAH metabolites, and urinary mutagenic activity. A number of studies have shown a significant correlation of exposure to PM(2.5) with these biomarkers. In addition, stratification by genotype increased this correlation. New multivariate receptor models, recently used to determine the sources of ambient particles, are now being explored in the analysis of human exposure and biomarker data. Human studies of both short- and long-term exposures to combustion emissions and ambient fine particulate air pollution have been associated with measures of genetic damage. Long-term epidemiologic studies have reported an increased risk of all causes of mortality, cardiopulmonary mortality, and lung cancer mortality associated with increasing exposures to air pollution. Adverse reproductive effects (e.g., risk for low birth weight) have also recently been reported in Eastern Europe and North America. Although there is substantial evidence that PAH or substituted PAH may be causative agents in cancer and reproductive effects, an increasing number of studies investigating cardiopulmonary and cardiovascular effects are investigating these and other potential causative agents from air pollution combustion sources.  相似文献   

15.
Adverse reproductive outcomes from exposure to environmental mutagens.   总被引:13,自引:0,他引:13  
The effect of environmental pollution on reproductive outcomes has been studied in the research project 'Teplice Program' analyzing the impact of air pollution on human health. Genotoxicity of urban air particles <10 microm (PM10) in in vitro system was determined by the analysis of DNA adducts. The highest DNA binding activity was observed in aromatic fraction, identifying DNA adducts of carcinogenic polycyclic aromatic hydrocarbons (PAHs) presumably diolepoxide-derived from: 9-hydroxybenzo[a]pyrene (9-OH-B[a]P), benzo[a]pyrene-r-7,-dihydrodiol-t-9,10-epoxide[+] (anti-BPDE), benzo[b]fluoranthene (B[b]F), chrysene (CHRY), benz[a]antracene (B[a]A), indeno[1,2,3-cd]pyrene (I[cd]P). Reproductive studies were conducted in both females and males. A study of the effects of PM10 exposure on pregnancy outcomes found the relationship between the intrauterine growth retardation (IUGR) and PM10 levels over 40 microg/m(3) in the first gestational month (Odds Ratio for 40-50 microg/m(3)50 microg/m(3)=1.9). Selected biomarkers were analyzed in venous blood, cord blood (chromosomal aberrations, comet assay) and placenta (DNA adducts, genetic polymorphisms of GSTM1 and NAT2 genotypes) of women enrolled in a nested case-control study. DNA adduct levels were higher in polluted vs. control districts, in smoking vs. nonsmoking mothers, and in GSTM1 null genotype, which was more pronounced in polluted district. No effect of air pollution was observed by cytogenetic analysis of chromosomal aberrations or by comet assay. The reproductive development of young men was followed by measures of semen quality, adjusted for ambient SO(2) exposure. The analysis identified significant associations with air pollution for <13% morphologically normal sperm, <29% sperm with normal head shape, <24% motile sperm. Analysis of aneuploidy in human sperm by FISH showed, aneuploidy YY8 was associated with season of heaviest air pollution. These findings are suggestive for an influence of air pollution on YY8 disomy. All these results indicate that air pollution may increase DNA damage in human population, which may be even higher for susceptible groups. Biomarkers of exposure (DNA adducts) and susceptibility (GSTM1 and NAT2) may indicate the risk of presumable low environmental exposure. Pregnancy outcome and semen studies imply that relatively low air pollution (higher than 40 microg PM10/m(3)) can significantly increase the adverse reproductive outcomes affecting both genders.  相似文献   

16.
Exposure to high levels of environmental air pollution is known to be associated with an increased carcinogenic risk. The individual contribution to this risk derived from specific carcinogenic chemicals within the complex mixture of air pollution is less certain, but may be explored by the use of molecular epidemiological techniques. Measurements of biomarkers of exposure, of effect and of susceptibility provide information of potential benefit for epidemiological and cancer risk assessment. The application of such techniques has been mostly concerned in the past with the carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) that are associated with particulate matter in air pollution, and has showed clear evidence of genotoxic effects, such as DNA adducts, chromosome aberrations (CA) and ras oncogene overexpression, in environmentally exposed Czech and Polish populations. We are currently extending these studies by an investigation of populations exposed to environmental pollution in three European countries, Czech Republic, Slovak Republic and Bulgaria. This pays particular attention to PAHs, but also investigates the extent of radically induced (oxidative) DNA damage in the exposed populations. Policemen, bus drivers and controls, who carried personal monitors to determine their exposures to PAHs have been studied, and blood and urine were collected. Antioxidant and dietary status were assessed in these populations. Stationary monitors were also used for ambient air monitoring. Amongst the parameters studied in the biological samples were: (a) exposure biomarkers, such as PAH adducts with DNA, p53 and p21(WAF1) protein levels, (b) oxidative DNA damage, (c) the biological effect of the exposure by measurement of chromosome damage by fluorescence in situ hybridisation (FISH) or conventional methods, and (d) polymorphisms in carcinogen metabolising and DNA repair enzymes. Repair ability was also measured by the Comet assay. In vitro systems are being evaluated to characterise the genotoxicity of the organic compounds adsorbed to air particles.  相似文献   

17.
城市群已成为中国城市发展的主要形式,城市化发展引发的一系列环境污染问题成为目前的研究重点之一,尤其是近年来明显的空气污染问题。由于传统的针对某一城市地区进行细致研究,难以解决在城市聚集的城市群下形成的区域性空气污染来源和影响机制等问题,使区域性空气污染造成的负面效应难以评估。通过构建综合评估模型范式,并运用空间分析,对京津冀168个区县2000年,2005年,2010年,2015年PM2.5人口暴露风险、人类活动对PM2.5的贡献、以及5种土地利用类型的"源汇"特征进行了实证研究。结果发现:(1)2000—2015年,京津冀城市群的人口暴露风险、空气污染分布、综合评估结果总体呈现北低南高的现象。(2)2000—2015年,各县域的人口暴露风险和空气污染的程度、范围呈上升趋势。不同的土地利用类型具有不同的源汇特征,且对污染的贡献不同。本研究通过综合评估模型范式对城市群或区域城市发展与空气质量的权衡关系模式开展量化解析,为城市的可持续发展提供了科学的范式和初步的实证示范。  相似文献   

18.
Recently environmental conditions during early parental development have been found to have transgenerational effects on immunity and other condition-dependent traits. However, potential transgenerational effects of heavy metal pollution have not previously been studied. Here we show that direct exposure to heavy metal (copper) upregulates the immune system of the blow fly, Protophormia terraenovae, reared in copper contaminated food. In the second experiment, to test transgenerational effects of heavy metal, the parental generation of the P. terraenovae was reared in food supplemented with copper, and the immunocompetence of their offspring, reared on uncontaminated food, was measured. Copper concentration used in this study was, in the preliminary test, found to have no effect on mortality of the flies. Immunity was tested on the imago stage by measuring encapsulation response against an artificial antigen, nylon monofilament. We found that exposure to copper during the parental development stages through the larval diet resulted in immune responses that were still apparent in the next generation that was not exposed to the heavy metal. We found that individuals reared on copper-contaminated food developed more slowly compared with those reared on uncontaminated food. The treatment groups did not differ in their dry body mass. However, parental exposure to copper did not have an effect on the development time or body mass of their offspring. Our study suggests that heavy metal pollution has positive feedback effect on encapsulation response through generations which multiplies the harmful effects of heavy metal pollution in following generations.  相似文献   

19.
Direct epidemiological observations suggest that exposure to high levels of urban air pollution may result in increased risk of lung cancer, sufficient to account for a few (approximately 1-3) percent of total lung cancer incidence. Extrapolation from occupational exposure and risk data suggests that among potential carcinogens present in polluted urban air, polycyclic aromatic hydrocarbons (PAHs) may make a major contribution to air pollution-associated lung cancer risks. The use of biomarkers of genotoxocity in large-scale population studies may help to reduce the uncertainty involved in the assessment of such risks, especially those associated with relatively low pollution levels such as nowadays found in many Western cities. Increases in biomarkers of exposure to urban air PAHs as well as biomarkers of early effects have been detected in situations of relatively high levels of air pollution (e. g., ambient PAH concentrations of the order of a few tens of micrograms per cubic meter). Evidence has also been found about the modulation genetic damage accumulation in different individuals by polymorphisms in genes involved in the activation or detoxification of PAHs, especially of polymorphisms GSTM1 and CYP1A1 genes. However, the inconsistencies in the currently reported effects of genetic polymorphisms suggest that additional factors may also be important in the modulation of individual susceptibility to the accumulation of PAH-derived genetic damage. Biomarkers studies in populations exposed to relatively low ambient PAH concentrations (below 20 microg/m(3)) have not demonstrated clear dose-related effects (e.g., on DNA adduct levels), possibly because of the existence of multiple sources and routes of human exposure to PAHs in addition to inhalation of urban air (including, for example, home heating, environmental tobacco smoke and diet), and the consequent difficulty of adequately and specifically assessing atmospheric air-related exposure. This makes it imperative that molecular epidemiology studies be designed in such a way as to allow adequate assessment of exposure to urban air PAHs at the individual level and over short-, medium- and long-term time periods which correspond to the expression times of different biomarkers.  相似文献   

20.
During the last decade, our knowledge of the mechanisms by which children respond to exposures to physical and chemical agents present in the environment, has significantly increased. Results of recent projects and programmes focused on children's health underline a specific vulnerability of children to environmental genotoxicants. Environmental research on children predominantly investigates the health effects of air pollution while effects from radiation exposure deserve more attention. The main sources of knowledge on genome damage of children exposed to radiation are studies performed after the Chernobyl nuclear plant accident in 1986. The present review presents and discusses data collected from papers analyzing genome damage in children environmentally exposed to ionizing radiation. Overall, the evidence from the studies conducted following the Chernobyl accident, nuclear tests, environmental radiation pollution and indoor accidental contamination reveals consistently increased chromosome aberration and micronuclei frequency in exposed than in referent children. Future research in this area should be focused on studies providing information on: (a) effects on children caused by low doses of radiation; (b) effects on children from combined exposure to low doses of radiation and chemical agents from food, water and air; and (c) specific effects from exposure during early childhood (radioisotopes from water, radon in homes). Special consideration should also be given to a possible impact of a radiochemical environment to the development of an adaptive response for genomic damage. Interactive databases should be developed to provide integration of cytogenetic data, childhood cancer registry data and information on environmental contamination. The overall aim is to introduce timely and efficient preventive measures, by means of a better knowledge of the early and delayed health effects in children resulting from radiation exposure.  相似文献   

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